1. Field of the Invention
The invention refers to an X-ray or infrared imagery apparatus, for radiography or scanning, comprising particularly:                a support for receiving a body to be examined,        a X-ray or light ray source provided with a focus for emitting a beam passing through a slit of a dose limiter driven in translation to sweep the body,        a detector driven in translation to be irradiated or illuminated by the beam sweeping the body in order to detect an intensity attenuated along the X-ray or light ray propagation path through the body,        an analog-to-digital converter to convert the detected intensities into data in order to determine an attenuation of the X-rays or light rays by the body, and        a programmed computer to process the data resulting from the conversion of the detected intensities in order to obtain an image representing the attenuation of the X-rays or light rays by the examined body.        
2. Description of the Related Art
An apparatus of this type is especially known from French patent application FR A-2 888 374 filed by the applicant. The detector is shaped with a detection rod and the dose limiter is driven in translation at the same speed and in the same direction as the detector to reduce the body exposure to the just necessary irradiation or illumination of the rod. The synchronous move of the dose limiter and the detector with respect to the fixed source tends to misalign these three elements. The misalignment effect is however kept at an acceptable level if the rays are emitted by the source with a low angle of divergence compared to the axial direction of the beam, thus enabling the source to be maintained in fixed position for a typical width sweeping. For a greater sweeping, for example twice the typical width, the effect of misalignment requires to successively carry out two sweepings starting from two fixed positions of the source.